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A Guide to Gear and Settings.

Gear and Settings

I wanted to talk to you about some important things that should help you with your gameplay. I wanna start off by talking about gear and then I’m gonna talk about in-game settings like sensitivity and some stuff about controls.

There are a lot of misconceptions about gear. Lots of people say gimmicky stuff like “good players will still be good even with crappy gear”.
These people have no idea what they’re talking about. I’m considered by plenty of people to be a good player. Not pro level by any means, but certainly competitive level, though lots of people would argue that I’m not good in any game mode that matters, but still.

I’ve actually tried playing with crappy gear, in friends’ houses and whatnot. For that matter, I used to own crappy gear. It never ended well. Sure, I might still be better than crappy players with crappy gear, but I’d get absolutely crushed by anyone with even a moderate amount of skill. Good gear won't make you good, no. But bad gear will make you bad.

So, since gear is in fact important, what that means is that you’re probably gonna have to spend some money. Luckily for me I don’t really have any expensive hobbies apart from gaming, so my money tends to accumulate to the point where I can afford to buy a bunch of crap all at once, but since not everyone is as lucky as me it might be that you’re gonna have to prioritize.
So, in other words, the most important stuff is what you’re gonna have to buy first.

So what is the number one important thing you need? The one thing you need to buy before anything else? I’m gonna tell you. Are you ready? Here it is: the most important thing to buy is… A DESK!

Bet you weren’t expecting that.

But yes, you really need a good desk. A crappy office desk won’t do since you won’t be able to fit both your mousepad and keyboard on it and still play at a comfortable sensitivity. So if you don’t have a good desk, go to IKEA and buy one. Like, right now. Seriously. A decent office chair might be a good investment as well.

The second most important thing is hard to rank, but it’s a close contest between mouse and mouse pad. Whichever you buy first should depend on the quality of whatever you have right now. If the skates on your mouse are worn out, go get a new mouse. If the skates are fine, go get a pad first.

You'll do perfectly fine just going by that and completely ignoring my post.

There is one thing you wanna keep in mind before anything else, and that is the quality of the sensor. The most popular sensors for gaming, and with good reason, are the Avago ADNS-3090 and its successor, the Avago ADNS-3310. ESR has a decent list of mice and their sensors which you can use for reference.

If you have a mouse in mind and don't know what sensor it has, type the following things in Google along with the name of the mouse: jitter, malfunction speed and lift-off distance. If it has jitter, don’t buy it. If it has a low malfunction speed, and for reference, the best mice have one of around four meters per second, don’t buy it. If it has a lift-off distance of above two millimeters, don’t buy it. Also make sure that it has no built-in acceleration or prediction that can’t be turned off, since those things will just mess with your muscle memory.

Rule of thumb is that if it’s a laser mouse it’s probably gonna suck. Optical mice are generally a lot higher quality and just as precise while lasers are generally bought by people who hear the word "laser" and automatically think that must be the best, because lasers.

I'm dead serious about this. Laser mice can be very precise, but optical mice are just as precise if not more, have the advantage of being tried and true and highly developed and they don't require special surfaces to track properly. Seriously, laser mice are very picky. They track quite well on glass, but if your standard cloth pad has the wrong color your shiny 9001DPI laser mouse will just say "nope". If your pad has different colors on different parts of your pad, then guess what: your laser mouse will track differently at different parts of your pad, likely with different accelerations since they all tend to have at least some. They also love to spaz out if you move them too fast, look at them wrong or insult their mother. So yeah. Get an optical, not a laser.

If jitter and such aren't an issue, you can go on to check some other features. Reading people’s opinions on a site like esreality is a good idea, because sites like that are frequented by competitive gamers who need to know their stuff and tend to have enough technical knowhow to know what they’re talking about.

There’s a lot of things to keep in mind here. One obvious thing is the shape of the mouse, which will influence things like how you grip the mouse. The winning shape seems to be the classic WMO shape, so try to go for a mouse like that. Ambidextrous and ergonomic designs should both be fine.

Second, either two side buttons, or none. I personally can’t play without the side buttons since I completely rely on them for weapon switching. If you don’t, get one without them since they can get in the way depending on how you grip the mouse. Also, they increase the weight. If the mouse has more extra buttons than that, like the Cyborg RAT, then it’s more than likely a gimmick mouse, probably a laser with over 9000DPI and you can safely ignore it. Unless you play mostly MMOs, in which case you'd do OK with it, but this is a Quake Live forum...

A DPI switch can be good for games like Battlefield 3, since that game has different sensitivities for things like tanks and turrets, so just messing with the in-game sensitivity might not be enough to get them all to feel the same. Otherwise it’s not necessary.

Lastly, you might wanna get some after-market mouse skates for it, unless it already comes with pure Teflon skates. Hyperglides are the best you can buy. Perfect Glide HD’s by PureTrak would be a good option, except for the fact that they have sharp edges and thus scrape your mouse pad, so yeah, don’t get them.
I have a Razer DeathAdder, and while it’s a great mouse it has one major issue. It gets dirty…
No, that’s actually not the real issue. The real issue is that IT WEIGHS A FRIGGIN’ TON!

Now, you might be wondering why this would be an issue. The reason is simple. More weight equals less control. The more weight an object has, the more momentum it has and also the more friction it has. Some people will say more friction equals more control, but no.
Any ease gained in simply stopping the mouse with the help of friction is instantly lost with the increased force required to do so, and either way you’ll require more force both to get the mouse to start moving and to change directions, which means you’ll have a harder time making small, accurate movements. In other words, worse control. For weight, you’ll probably wanna shoot for a mouse weighing around 80 grams or less. The DeathAdder weighs twice that.

Currently the best mouse on the market seems to be the Zowie FK. Indeed, Zowie mice currently seem to smash most of the competition. I am personally gonna wait for the Ninox Aurora and buy that to replace my DeathAdder.

For the hell of it, here's mathematical proof that lighter mice are superior (for the unbelievers):

Still the exact same factor. You still require almost twice the amount of force from your hand to stop the mouse. That means the extra friction given from a heavy mouse does not help you stop the mouse. Some people think more friction or weight gives more control. Simple mathematics implies otherwise. Lower weight gives you both better glide AND better control.

There’s first one big choice you have to make that will heavily influence how difficult it will be to find a top-quality mousepad: Hard-surface, or cloth?
It’s very difficult to go wrong with a hard-surface pad. QPAD seems to currently make the best ones, and they consistently deliver pads that are of comparable size to the larger cloth pads, and you do want your mousepad to be large (40cm wide), or else you will be limited in what sensitivities you can use. But a SteelSeries will be fine too (Icemat is legendary).

If you wanna go absolutely nuts with a hard surface pad you could go get a CAD mousepad like the KomaQ G-Pad tempered glass mousepad, but be prepared to make some phonecalls and spend a lot of money.

The problem with hard pads, and make no mistake, this applies to ALL of them, is that they will wear out your mouse skates rather quickly. You might counteract this by buying some kind of silicate spray (yes, that's a real product) or anti-friction liquid (that one can be used with cloth pads as well, but if you do then ONLY put it on the skates. If you put it on the pad the cloth will absorb it and ruin the pad), which will be a lot cheaper than constantly buying new skates.

Or you can buy a cloth pad. The major advantage cloth has is ease of transportation. You can just roll them up. But do yourself a favor and don’t roll them up too tightly or you’ll deform them.

The major problem with cloth pads is that it’s incredibly difficult to find ones with comparable glide to hard surface pads. You can’t simply go by popularity on this one, and asking people will not help you as much as you might hope for the simple reason that most people quite frankly have no clue what they’re talking about. Probably because they've never used anything better than what they're recommending and thus don't know that better exists.

When I first switched from my QPAD HeatoN to a SteelSeries QcK Heavy the sheer drop in quality I experienced was ridiculous. It was so horrible that I immediately went and ordered a Razer Goliathus, only to find that it was pretty much the exact same as the QcK Heavy, and these are the two most popular cloth pads. Note that I had pretty much ruined the surface of my HeatoN by being an idiot and scrubbing it with a rough brush while cleaning it, and it was still blatantly superior. Of course, if you’ve never owned anything better than the QcK or the Goliathus I doubt you’d notice, but you wouldn’t notice how much worse a 60Hz LCD screen is in comparison to a 160Hz CRT if you’ve never owned anything better than a 60Hz LCD either.

The problem with the pads I mentioned is the control. They give you trouble both in switching direction and with the starting motion. It’s basically a feeling of inertia, like something is resisting the motion.

Fortunately there are a few cloth pads with quality comparable to the hard-surface ones. Just a few.
While I haven’t tried it myself, people who have used the PureTrak Talent say it is just as good as the pads I’m about to mention. The first cloth pad I used that was as good as my QPAD was the Zowie G-TF SpawN. There’s a “speed edition” too, which (as of october 2013) is what I'm currently using, but good luck getting that one to lie flat on the desk. Anyway, the SpawN is great and also easy to clean since it doesn’t absorb any liquids, however, it does have a problem. The rolled up edges can chafe your wrists. I got a blister after the first couple of days I used it. This can be avoided by keeping your wrist slightly raised above the pad when making large motions, so it's not a deal breaker.

The other option you have is to import from a small Japanese company called Artisan. They are a group of materials science engineers working together with pro-gamers who specialize in cloth-pads. I made a short review of the Artisan Hayate, so you can tell the glide is ridiculously good.

The most popular Artisan pads are the Shiden-Kai, the Hien and the Hayate. Luckily, Artisan themselves have a nice comparison chart, giving each pad a relative rating in categories such as “speed of initial motion”, “smoothness” “horizontal/vertical glide” and “stopping”. They also hilariously have a category called “Upgradability from QcK”.

The problem with Artisan pads is that they're not made to last. The Hayate's glide will probably start deteriorating after 3 months. Also, some of their pads, like the Raiden, don't work with all mouse sensors, which sadly includes all the best ones. They've stated outright that they care more about quality of glide than compatibility with top of the line mouse sensors, which is likely part of the reason they haven't gotten very famous.

Do note that they seem to have translated their whole site to English with Google Translate, so it can be a bit hard to navigate. Some of their pads are available on Amazon if you’re worried about importing.

QPAD has recently launched their QPAD FX line of pads, which are quite affordable and come in sizes from "small" to "good luck fitting this thing on your desk". Glide on a freshly bought one is as good as or better than a Zowie G-TF Speed.

There’s one last important thing about mousepads that I wanna cover before moving on, and that is maintenance and cleaning. I like to keep my gear covered in bubble wrap when I’m not using it, but no matter what you do your mouspad will start accumulating dust, dirt and sweat, and the glide will worsen as a result, so eventually you’ll wanna clean it unless you feel like buying a new pad.

There are two cardinal rules that you must never, ever break.

Rule number one: Never, ever use hot water on a cloth pad. They usually contain some kind of rubberized material, and hot water WILL deform it. Use only lukewarm water. Hell, while you’re at it, only use lukewarm water on hard pads too, just in case.
Rule number two: Never use any kind of rough brush. Either use your hands or a soft sponge. Anything rough will ruin the texture, which will worsen the glide.

You could probably get away with just chucking the pad into a washing machine, as long as you make sure to set it to max 30 degrees Celsius and whatever setting is for fine or sensitive materials. If you wanna do it by hand you should have no trouble washing it with soap, though your mousepad might smell like perfume afterwards.
This about covers it for mousepads.

Currently there are only a few gaming monitors on the market worth considering, but I’ll still go over the basics just to make this future-proof.
The first thing you wanna prioritize when buying a monitor is refresh rate. Now, some people will tell you that a higher refresh rate doesn’t really matter. They’ll say something along the lines that the human eye can only see 24 frames per second or some similar claim.

These people are idiots.

First of all, 24 frames per second is the average speed required for something to stop looking like a bunch of still images and start looking like actual motion. It’s not some arbitrary cutoff for what the human eye can see. Jet pilots have been able to distinguish individual frames at speeds up to 300 frames per second. I play at 144Hz and I can still tell individual frames apart if things on the screen are moving fast enough. And even if this weren’t the case you can still “feel” the difference. Your mouse movements and aim will simply “feel” smoother, and improve consequently.

The trick movie makers use to make their movies look smooth even at low framerates is that they use massive amounts of motion blur, and motion blur is horrible for gaming, since it will simply make it take longer for you to distinguish enemies when you’re moving around, and consequently lower your reaction speed. There’s a trick you can use in combination with 3DVision 2 monitors to enable something called “Lightboost” in-game, which causes the backlight to strobe and eliminates all motion blur. It’s quite an amazing trick. If you have a compatible monitor, go to this link, read it and download ToastyX's Strobelight app.

The second most important thing you need to consider when buying a monitor is input lag. The concept of input lag is simple: how long does it take for something to happen on your screen after you click with your mouse? If it’s above 5ms the monitor probably wasn’t meant for gaming. The best ones have less than 1 or 2 milliseconds.

Anyway, if you’re reading this in early 2013 you can ignore all that stuff, because as I told you before, there are currently only two monitors on the market worth considering if you want one specifically for gaming. The BenQ XL2411T 24’’ monitor, and the ASUS VG278HE 27’’ monitor. Both of them are 144Hz 1080p monitors. The difference is that the BenQ has 1ms input lag to the 2ms of the ASUS, though that can vary depending on what screen settings you use. The lowest input lag should be with native resolution and 144Hz.
Also, the ASUS is bigger and costs about twice as much. I got the ASUS for no other reason than that it was bigger. Bigger screen means bigger targets means easier to hit. If you feel any differently than me about that, get the BenQ, since it’s basically superior in every other way.

You could also consider getting an old CRT on eBay or similar. Good for gaming, bad for eyesight. Might be easier on the wallet.

And that’s basically all you need to know. It might be worth considering that gaming monitors won’t have the best image quality since better panels quite simply have a helluva lot more input lag, to the point where you can actually see that it takes time for your inputs to register on screen. Anyone who has ever played Smash Brothers or Guitar Hero on a plasma TV will know what I’m talking about. But as a hardcore gamer image quality shouldn’t really be your priority. And anyway, to me it already looks great.

Moving on, the next most important thing is your headphones. Just having them is comparable to using a wallhack when compared to not having them. I only rank them this low because you likely already have a perfectly good pair that came with your phone or music player and thus don't need to buy any. If you don't care about sound quality and listening to music, then almost literally any headphones will do. Preferably earbuds or in-ear monitors in that case since you don't have to mess around with getting them to sit right and they have a surprisingly good soundstage.

If you care about sound quality, then there are a ton of audiophiles out there who can help you pick a good pair of headphones or IEMs. Not so luckily, I am not what you’d call an expert here, and also, some audiphiles believe in some very strange pseudo-scientific things like "burn-in" (which is basically audiophile homeopathy).

One thing to keep in mind is to never buy a “surround sound” headset. It’s an expensive gimmick. Try out any stereo headset or headphones and listen to the “virtual barbershop” sound clip, either on the official site or on youtube. You’ll immediately see why surround sound headsets are a waste of money.

3D games need "System Input" to be set to "8 Channels" in Windows/sound card drivers to output positional audio accurately (that is 7.1 audio). Note: this is not the same thing as setting the "Output Device" to 7.1 speakers. Output Device needs to be "Headphones".

Note that having 8CH/7.1 when you're listening to music might be a bad idea if you're an audiophile. You should use 2CH/stereo for that, but try out both to see if there's a noticeable difference when listening to music.

And finally we get to the keyboard. Now, the keyboard is a special case, since what you’ll be considering is not something like input lag, since those things don’t really matter as much here. There are only two things to really consider with keyboard. One of them is comfort, the other is n-key rollover. All USB gaming keyboards have what’s called 6-key rollover. What that essentially means is that you can hold down 6 keys at the same time and all keypresses will be registered. However, this is a little bit misleading since generally only four keys will always have 6-key rollover, and those are the WASD keys. If you use an alternate scheme like ESDF or RDFG then you might find that you can’t do things like crouch and move forward at the same time, or not reload while moving to the right. Sometimes certain combinations of keypresses won’t work even with a WASD scheme.

The only way you can be sure to avoid this problem is by using a mechanical keyboard plugged into the PS/2 port. Not only will this give you full n-key rollover, mechanical keyboards are also a lot more durable than standard plastic-dome keyboards and they also just feel nicer.

Now, there are a few different types of mechanical keyboards. Specifically there are different types of mechanical switches. Fortunately, the Cherry switches most manufacturers use are color coded for your convenience. There are a bunch of different colors, based on things like tactile feedback, clicking noise and required force to press down keys.

The two colors that are specific for gaming as opposed to typing are the black and red switches. These feel the same no matter how much you push them down, in other words they have no special tactile feedback, and they also don’t have a ridiculously loud clickety-click sound when you type, although they do still make noise.

The difference between them is that they require different amounts of force to press down. The black switches require an average of 55 grams of weight to press down while the red ones only need around 45 grams. You might immediately conclude that the red ones are better, but that’s not necessarily the case. You’re probably resting your fingers on the movement keys while playing. If you do that, and your hands are heavy enough or you're simply resting too much of your weight on them, then with the red switches you might just find yourself suddenly moving in a random direction because the key you were resting your finger on requires so little force to press down you did it completely by accident. Of course, if you don't have this problem, then why not Reds?

Now, just because they're specifically for gaming doesn't mean they're necessarily the best for them. Blue and Brown switches are the same as Black and Red, except you can feel when they actuate (as in, you know for sure when the key has been pressed). They do not require any more force to press down, and I personally can't think of why having that feeling would be bad. Zowie Celeritas is a nice mechanical keyboard that has the option for either Brown or Red switches. I've got the version with Browns and I love it.

That covers it decently enough. “Mechanical” and "Black/Red/Blue/Brown switches" is basically all you need to remember when buying a gaming keyboard.
And it also pretty much covers it for gear, unless you need a microphone, in which case I say just get a Logitech Desktop Microphone, or if you need a whole new computer in which case you’ll really wanna ask for help on some overclocking site.
What remains are the settings, where I’ll cover the easy stuff first and finally mouse sensitivity and Field of View.

Generally you want to balance your settings to give you a framerate as close to your monitor’s native refresh rate as possible. This might be unfeasible in more demanding games unless you have a lot of money to burn, but at least try to keep it above 60 frames per second.

In a non-demanding game like Quake Live you might experience frame-rate drops on a high-end machine. If this happens to you it’s pretty much certain that your processor is being throttled. If that seems to be the case, go to Power Options in Windows and change the mode to “High Performance”. This will make sure that your processor doesn’t throttle down to a lower power state just because your computer doesn’t think Quake is demanding enough. In Quake you should never drop below 125 FPS on any decent computer unless you have this specific problem.

One other thing to consider is visibility vs image quality. It’s quite simple: the easier your enemy is to see, the easier they are to shoot.
In Quake it’s no problem to optimize for visibility. Just turn textures off with picmip and make sure that your enemies are all a uniform bright color. Don’t forget to turn off things like bob and whatnot, though I shouldn’t have to tell you that.

Before we get to sensitivity there’s still the matter of controls to discuss. Unlike with sensitivity, you should not have a universal control scheme for all games. More specifically, not for all types of games. Trying to have the same keybinds with an arena shooter like Quake and a military shooter like Battlefield will just mess you up, since your muscle memory won't work unless the buttons do the exact same thing for both games. I can give you examples of my own settings in Quake and Battlefield to give you an idea of what to keep in mind, though.

In Quake Live I play with an RDFG setup. Firstly it feels a bit more comfortable for me to have my hands closer together when playing. Secondly, the thing to keep in mind in Quake is that most of your keybinds will be dedicated to weapon switches, and switching away from a WASD configuration will open up some keybinding options on your left side. The only problem you need to overcome is where to put your crouch and walk keys. Not really a big problem as it’s not that hard to move up a step with your pinky finger and use something like S and X or S and Z. Might take a bit of getting used to, though.

These are special cases though, and a WASD configuration should be perfectly fine. There are a couple of things that everyone should do, however. Everyone should switch the jump key to MOUSE2. Jumping in Quake Live is something you do constantly, and timing your jumps is important. Mice generally have a polling rate of 500Hz to 1000Hz, while keyboards at best might have one of 200Hz. And not only that, timing key presses with one hand to the movement of another hand is a lot harder than clicking and moving with the same hand. These things combined mean that both rocket and strafe jumping are a lot easier with jump bound to your mouse.

Consequently you need to rebind +zoom. The obvious candidate here is the spacebar. I use mouse-jump with space-zoom in Battlefield 3 as well with no issues whatsoever.
There are some people advocating using the keyboard to fire. While they do have a point in that it makes it so that you are not constantly pressing down on your mouse while shooting an enemy I find that it really screws you over with weapons where you need to precisely time your clicks. Specifically, I tried it for a couple of months and while it felt good for the LG my railgun accuracy suffered horribly. I wouldn’t recommend it.

As for Battlefield 3 having an RDFG configuration made things absolutely terrible. The hard part was simply moving around fluidly. You have to find good bindings for pretty much everything, and no matter how I tried I couldn’t find any combination of keybinds that made the acts of crouching, proning and sprinting comfortable. Simply having access to the CTRL button made life a lot easier for me.

Having jump on mouse2 and zoom on space works quite well in BF3 as well, however. There are also some small changes to the default settings that will help you plenty. Firstly, rebinding your primary and secondary weapons to your mouse 4 and 5 buttons is probably something you should do if your mouse has those buttons. Panic-switching to pistol and then quickly back to your main weapon becomes quite easy then. Having them around your movement keys doesn’t really work in this type of game since there are other important commands that need those keys there already, like spotting enemies and getting in and out of vehicles.

Another thing you should consider is rebinding your reload key to one you can press with your thumb, like V for instance. Doing this means that you’ll be able to reload while moving to the right, which makes it a lot easier to survive firefights since you can still dodge while reloading. Also, bind your melee attack to the mouse wheel button. Just do it. There’s no reason not to.

And now for the part everyone has been waiting for. Mouse sensitivity. I’ve already given you a decent range to pick from in an earlier guide, but it’s time to go a bit more in-depth.

I'm gonna format this a bit differently, since this section is pretty big compared to the others and I don't want to waste your time when you're looking for the info you want.

Windows, Driver and DPI Settings

You wanna start out with making sure both your Windows and driver sensitivities are set to their default values. This will make sure your cursor doesn’t skip pixels or anything silly like that. Then you wanna make sure that Enhance Pointer Precision is turned off. This will get rid of the “floaty” feeling you’ll otherwise encounter in games that don't use raw input. Lastly, get the Mouse Fix for whatever version of Windows you’re using. Google it.

Now you wanna adjust DPI. Since your Windows and driver sensitivities should be at default, your best option for adjusting the sensitivity on the desktop is changing the DPI. Adjust the DPI so that your desktop sensitivity feels similar to your target in-game sensitivity. What value will feel right will depend on your monitor's resolution. The extreme ranges should be around 400DPI for low sens (40cm/360) players and 1800 for high-sens (20cm/360) players. When I wrote this I had it set to 900DPI and I played at 33cm/360 with FOV 90. I currently use 800DPI with my tried and true 45cm/360 at FOV 100.

You can always change this later if you change from a high-sens to a low-sens config or vice-versa. Use simple multiplication to keep your sensitivity the same; if you halve your DPI, double your in-game sensitivity to keep it the same. If you use m_cpi like I recommend in the next section, this becomes a non-issue.

In-Game Settings

First thing I would do is pick a Field of View. Sensitivities are usually measured in distance for a full 360 degree turn (cm/360), but 40cm/360 at 130 FOV is way, way slower than 40cm/360 at 90 FOV, even though it's the same amount of mouse movement for a 360 degree turn. The reason for this is that you have a lot more of those 360 degrees on your screen at any one time with FOV 130, and thus your actual viewpoint will change less over all. The reason zoom feels the same is that zoom sensitivity uses a trigonometric formula to scale your sensitivity to a lower FOV so that it won't suddenly feel like your sensitivity increased to a million when you zoom in.

The default FOV of 100 is quite good (it's what I use), but a lot of people swear by a FOV of 90 for higher railgun accuracies or 110 for better situational awareness.

When you’ve picked a FOV that you like you should open your Quake Live config file in a text editor. Look up your mouse DPI and write m_cpi x, where x is your DPI (CPI). This will make it so that you won’t have to play around with a ruler when figuring out what sensitivity you have.

The result of using m_cpi with the correct value is that the number you type with the /sensitivity command will be your actual degrees per centimeter (note: deg/cm is NOT cm/360, but is easily converted to it) rather than some arbitrary number.

Chances are you already have a sensitivity picked out. You can convert it to the new system with a simple formula:

new_sens = old_sens * ( old_yaw * m_cpi / 2.54 )

Unless you’ve been mucking around your config with settings you really shouldn’t be messing with, your m_yaw should be 0.022. Thus you just type your current sensitivity*(0.022*your DPI/2.54) into Google and make the resulting number your new sensitivity.

Example: When I first changed systems my sensitivity was 1.5. My DPI was 900.

1.5 * ( 0.022 * 900 / 2.54 ) = 11.7

That is 11.7 degrees per centimeter rounded up. So my new sensitivity would be 11.7 (I have since lowered this).
To convert degrees per centimeter to centimeter per 360 degrees, use this formula:

360 degrees / ( degrees / cm )

The degrees cancel out and the centimeters get moved to the numerator.

Example: 360 / 11.7 = 30.8

In other words, it takes me approximately 30.8 centimeters on my mousepad to turn 360 degrees in-game. Simple, right?

NOTE: If you want your sensitivity in the old system back you can easily get it by dividing new_sens with everything after old_sens.

old_sens = new_sens / ( old_yaw * m_cpi / 2.54)

Choosing a Good Sensitivity

Now, what if I want to figure out what's a good sensitivity for me? This is, as you might have guessed, rather important.

The standard sensitivity ranges for Quake Live are 40cm (low-sensitivity) to 20cm (high-sensitivity) for a 360. Anything above or below that range is considered extreme. Strenx, for instance, needs 50 centimeters to make a full turn. This is generally not recommended since it becomes hard to strafe jump and hard to track enemies moving around you. On the other extreme, a sensitivity higher than 20/360 is bad because at that point it will get a lot harder to aim. I don’t know of any pro with a higher sens than that in either Quake Live or Counter-Strike, and these are the games where general consensus states the top aimers play.

So how do you calibrate your sensitivity as fast as possible? Simple. Start by playing a few games with 40/360, then play a few games with 20/360. Always start with the lower sensitivity, since otherwise both might feel like “low-sensitivity”. This is because casual gamers usually start out with something ridiculous like 5cm/360. Starting with 40 will make 20 seem comparatively high.

Now, to calculate. To quickly make your sensitivity 40/360 (or any other) without messing around with a ruler, make sure you're using \m_cpi <your DPI> and then use this formula:

360 degrees / centimeters = degrees per centimeter

Simple dimensional analysis.

Example: I want to play at 40cm/360. I calculate that:

360 / 40 = 9

9 degrees per centimeter. Type /sensitivity 9 in your config or console and play a few games to get used to it. Do note that this is quite low, and you won't be able to make a full 360 degree turn on your mousepad with only one sweep if your mousepad is small.

Now try 20cm/360.

360 / 20 = 18

Type /sensitivity 18 in the console and play a few more games.

Which one did you prefer? Was your aim a lot better with 40? Was your movement a lot better with 20? Start adjusting and try to find the sweet spot where your aim doesn’t get worse and your movement doesn’t get better, or go for one of the extremes. When you're done, spend at least a week with your new sensitivity before trying to adjust it again. I recommend spending at least a week with any new sensitivity before attempting to adjust it. This is so that you actually have time to get used to it and also so that you don't develop the terrible habit of constantly changing your sensitivity and thus never letting your brain adapt to one. Seriously, it's very hard to break that habit, so don't fall into it.

Changing FOV Without Ruining Your Sensitivity

What about changing FOV in Quake Live? You might want to increase/decrease your FOV and still keep the same feel. Again, remember that a cm/360 value means different things with different fields of view. 40cm/360 is very, very low if you have your FOV at 130, but if you were to lower your FOV to, say, 13, then the slightest twitch of your mouse would move your viewpoint several screens. Quake Live won't scale your sensitivity based on your FOV. It will do so for zoomfov, however, and the algorithm is available and can be used for normal FOV changes.

Here the FOV degree values you type in are converted to radians so that the algorithm can be used with Google's calculator, since Google and most calculators use radians instead of degrees. The normal algorithm uses FOV / 2 instead of FOV * π / 360 (180 degrees = π radians).

If you use the new system with m_cpi you want to convert to the old system first. See the note in the In-Game Settings section above for the conversion formula.

This formula might look intimidating, but really, all you need to do is copy everything after the = sign into Google or WolframAlpha and replace old_sens, new_FOV and old_FOV with their respective values and the new_sens you want will pop out. There's no need to know what the formula means or to type it in manually. Copy, paste, replace, press enter.

Converting Quake Live Sensitivity to Other Games

So now you have a good sensitivity for Quake. How do you make sure that you have the same sensitivity for the other games you play?

There are a couple of methods. If the math is readily available you can use an online converter like this one. Remember, if you use m_cpi you probably need to convert your m_cpi sensitivity back to the old system before using a calculator, unless the calculator you use accepts m_cpi inputs.

If the math isn't easily available you can use the following trick:
First, with a ruler or similar, measure how far you have to move your mouse to change your viewpoint one full screen. This is easily done by standing near a wall and letting the very edge of that wall be at one edge of your screen, then moving the mouse until the edge of that wall is at the other edge of your screen. After that, fiddle with the sens in the other game until you can do the same there with the same distance moved with your mouse.

It’s worth going through the effort to make everything the same across games and at different FOVs, because when you do you will not have to re-learn the muscle memory. Repetition is the key to perfection. Remember that. Always.